At least one embodiment of the invention relates to an energy storage device comprising a plurality of magnets configured to stabilize an energy storage element such as a flywheel. The flywheel is suspended in a gaseous medium or vacuum via a non-physical contact or support such as via superconducting magnets.
High temperature superconducting magnetic bearings are used for the rapid rotation of flywheels. High temperature superconductors such as those with YBCO or Yttrium Barium Copper Oxide bearings have to be cooled but are stable without electronics control. Superconducting magnetic bearings can be self-regulated (by an electromagnetic field) without monitoring and electromagnetic regulation/attraction of the rotor. Control and specification of the properties of HTS magnets such as levitation pressure (load), restoring forces (stiffness) and damping are determined by the magnetic interaction design. See HTS Magnetic Bearings in Prototype Application F. N. Werfel, U. Floegel-Delor, T. Riedel, R. Rothfeld, D. Wippich, and B. Goebel are with the Adelwitz Technologiezentrum GmbH (ATZ), Adelwitz, Germany. Manuscript received 20 Oct. 2009. The general teachings of flywheels is disclosed in U.S. Pat. No. 5,065,060 to Takahashi et al, the disclosure of which is hereby incorporated herein by reference in its entirety.